Skip to main content

Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

See other formats

side from the snowfields and cirques about Mt. Castner1 and other mountains between College Fiord and Unakwik Inlet.
Applegate's map of Yale Glacier in 1887 shows it terminating somewhere between College Point and the present stand; but since he did not approach the glacier nearer than 12 miles, about the same as Vancouver did in 1794, it is impossible to draw any conclusions from these early maps concerning the behavior of Yale Glacier prior to 1898.
From the photograph (PL CXXHI) taken by Mendenhall in the latter part of April, 1898, it is evident that Yale Glacier was in almost exactly the same position as at .present. The rock ledges were exposed beneath the middle of the ice front and the eastern half exhibited "the rough pinnacled front of a still-advancing stream. Its western front is of dead-white ice."
On this same occasion Castner went on snowshoes some distance up the margin of the Yale Glacier, which may perhaps show that it was then less severely crevassed than in 1910 when traveling upon its surface was impossible. But our visit was at a later season when the snow had disappeared.
Glenn gives a vivid description of Yale and Harvard glaciers as he saw them in 1898 from College Fiord. "The day was dry and clear. Directly in our front was the most imposing sight we had yet seen—I might add more imposing than any we saw during the season. Glistening in the sun were two large glaciers, which we named the 'Twin Glaciers,' * the pair being separated by a short ridge or hogback that runs down to salt water. In front of the one on our right the sea ice extended for over 3 miles, while in front of the other this sea ice extended at least twice that distance. This ice was covered with snow several feet in depth. We soon discovered that it would bear up the weight of a man and that we could make no headway against it with the boat. Each of these glaciers is what is termed 'live' or 'working' glaciers. The front of each was an almost perpendicular mass of ice, from which immense pieces were constantly breaking off and falling into the sea with a great roaring noise, due principally to the action of the tides."
The map of Yale Glacier by Gannett, the description by Gilbert, and the photographs by other members of the Harriman Expedition in 1899 show clearly that in all major features of position Yale Glacier had at that time assumed the general conditions which prevailed in 1910. The rock ledges beneath the center of the glacier are seen in the photographs, and Gilbert indicates that there were barren zones at the margins. He explains the dirty ice near the northwestern side of the glacier as follows: "A blackening, west of the middle, by glacial drift suggests that a rock knob may lie near the surface, ready to develop into a nunatak or island if the glacier shall diminish."
The photographs and descriptions by Grant in 1905 and 1909, and the map by Higgins in the latter year show that Yale Glacier maintained essentially the same conditions during the decade following 1899. The narrowness of the barren zones in 1909 leads Grant to conclude that the eastern margin was slightly farther advanced in that year than in 1898 and 1899.
In 1910 Yale Glacier was advancing strongly. By July 15, the southeastern edge had advanced 750 feet beyond its position in 1899, as was shown by comparing conditions
1 This peak and the adjacent glacier were named in 1910 for Lieut. J. C. Castner of the U. S. Army. a Now called Yale and Harvard Glaciers.